Anger across the Muslim world over an anti-Islamic film continued Tuesday, with a rare appearance by the head of Lebanon's militant group Hezbollah only adding fuel to the fire.

Tens of thousands of protestors gathered Monday to hear a 15-minute speech by Sheik Hassan Nasrallah calling for the nationwide demonstrations to continue.

Nasrallah said the United States must be held accountable for the anti-Islamic film that's creating strife between Muslims and Christians.

"Our anger today is not a useless movement but the start of a serious movement that must continue all over the Muslim world in defense of the prophet of God," he said.

CBN News Mideast Bureau Chief Chris Mitchel offered his analysis of the Muslim riots on "The 700 Club," Sept. 18. Click play to see his comments.

Western embassies around the world remain on high alert as the anti-American protests continue in at least eight countries.

Iran's top leader, Ayatollah Ali Khamenei, appeared on state television and urged Western leaders to block the film out of respect for Muslims.

"They should prove they are not accomplices in this great crime," Khamenei said. "They cannot prove this through words. They should prove this in practice. They should prevent such offences."

Meanwhile, tensions between Iran and Israel continue to grow.

Gen. Mohammad Ali Jafari, commander in chief of Iran's Revolutionary Guard, recently warned that Iran would close the Strait of Hormuz if it was attacked.

Now naval powers from 25 countries, including the United States and Great Britain, are in the Persian Gulf.

While they claim they're there to conduct a 12-day minesweeping operation, experts believe they're preparing to protect the strait.

"Despite the fact that the Department of Defense indicated that it's not directed at Iran … it is sending a good signal to potential adversaries that we can deal with any threat that's thrown at us," Scott Truver, an expert on navy operations and mine warfare, told "PBS Newshour."

Nearly 18 million barrels of oil are transported daily through the 21-mile wide waterway.

The conflict in the Mideast is leading to rising gas prices here at home. Prices usually decline after Labor Day but instead they've been steadily rising for weeks.

They now stand at an average of $3.87 a gallon. Experts say prices could start to decline now that refineries have switched to the less expensive winter gas blend.